View Full Version : Purely SPL box

03-26-2006, 09:49 PM
We just installed my friend's type R in a 2.5 cubic foot box tuned to 32hz, sounds GREAT to an mtx 801d but he wants to have an SPL box (purely) to see what he can do. So, if we use the same exact dimensions and same port size (13"X3") the port length just changes to 24.4" deep instead of the 37" we have now. Would this be a decent SPL box? That would be 2.5 cubes tuned to 38hz? Should we tune higher, around 42-44hz maybe? Let me know what you guys have done. I know it's a type R, but we're just trying to have fun with it, thanks.

03-26-2006, 09:52 PM
higher tuning = higher SPL #s.......bass below the tuning frequency may damage your sub

you will also miss out on the low/deep bass (which makes bass appear louder)

03-26-2006, 09:54 PM
For a spl box, shouldn't you tune to the natural frequency of the car?

03-27-2006, 12:55 AM
biggest difference in db played inside and outside the car?^

03-27-2006, 08:01 PM
so ur saying, higher the hz( in terms of box tuning ), louder in db, will this affect sub performance and will it be louder on the outside of the vehicle...

03-27-2006, 10:32 PM
One method is to meter a speaker in a preferably sealed enclosure in an open space that doesn't benefit from cabin gain. Plot the output at the common range of frequencies. Put the same box in the vehicle and plot the output. The frequency that was boosted the most should be around the resonant frequency.

IDK if this is accurate or not since I've never tried it, though. Seems like it would work.